It's part of the process of starting a new tank. Nothing strange. The lawnmower blenny might starve if there's not much gha (green hair algae): they don't do well in a tank with little algae to eat (don't eat film algae like snails).
Start measuring phosphate and nitrate. Don't let either go to zero. If either goes to zero, then your ugly phase will go to a extreme PITA phase. Don't make drastic changes: slow and deliberate.
Consider getting a fish that eats mysis shrimp. In the first pic, a see a hint of purple on the right side that made me think you have a Royal Gramma.
What are your methods of exporting nutrients? A flow of nutrients (fish food in and skimmer, macro-algae, and/or ATS out) is preferred to stagnate nutrients.
What are you planning to keep in your tank long-term?
